Patents by Inventor Yusuke Hiwasaki

Yusuke Hiwasaki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10515643
    Abstract: In encoding, a frequency-domain sample sequence derived from an acoustic signal is divided by a weighted envelope and is then divided by a gain, the result obtained is quantized, and each sample is variable-length encoded. The error between the sample before quantization and the sample after quantization is quantized with information saved in this variable-length encoding. This quantization is performed under a rule that specifies, according to the number of saved bits, samples whose errors are to be quantized. In decoding, variable-length codes in an input sequence of codes are decoded to obtain a frequency-domain sample sequence; an error signal is further decoded under a rule that depends on the number of bits of the variable-length codes; and from the obtained sample sequence, the original sample sequence is obtained according to supplementary information.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: December 24, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yutaka Kamamoto, Yusuke Hiwasaki, Masahiro Fukui
  • Patent number: 10269363
    Abstract: A normalization value calculator 12 calculates a normalization value that is representative of a predetermined number of input samples. A normalization value quantizer 13 quantizes the normalization value to obtain a quantized normalization value and a normalization-value quantization index corresponding to the quantized normalization value. An quantization-candidate calculator 14 subtracts a value corresponding to the quantized normalization value from a value corresponding to the magnitude of each of the samples to obtain a difference value and, when the difference value is positive and the value of each of the samples is positive, sets the difference value as an quantization candidate corresponding to the sample. When the difference value is positive and the value of each of the samples is negative, the quantization-candidate calculator 14 reverses the sign of the difference value and setting the sign-reversed value as an quantization candidate corresponding to the sample.
    Type: Grant
    Filed: February 7, 2011
    Date of Patent: April 23, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masahiro Fukui, Shigeaki Sasaki, Yusuke Hiwasaki, Shoichi Koyama, Kimitaka Tsutsumi
  • Patent number: 10096327
    Abstract: A frequency-domain sample interval corresponding to a time-domain pitch period L corresponding to a time-domain pitch period code of an audio signal in a given time period is obtained as a converted interval T1, a frequency-domain pitch period T is chosen from among candidates including the converted interval T1 and integer multiples U×T1 of the converted interval T1, and a frequency-domain pitch period code indicating how many times the frequency-domain pitch period T is greater than the converted interval T1 is obtained. The frequency-domain pitch period code is output so that a decoding side can identify the frequency-domain pitch period T.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: October 9, 2018
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Patent number: 10083703
    Abstract: A frequency-domain sample interval corresponding to a time-domain pitch period L corresponding to a time-domain pitch period code of an audio signal in a given time period is obtained as a converted interval T1, a frequency-domain pitch period T is chosen from among candidates including the converted interval T1 and integer multiples U×T1 of the converted interval T1, and a frequency-domain pitch period code indicating how many times the frequency-domain pitch period T is greater than the converted interval T1 is obtained. The frequency-domain pitch period code is output so that a decoding side can identify the frequency-domain pitch period T.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: September 25, 2018
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Publication number: 20180182405
    Abstract: A frequency-domain sample interval corresponding to a time-domain pitch period L corresponding to a time-domain pitch period code of an audio signal in a given time period is obtained as a converted interval T1, a frequency-domain pitch period T is chosen from among candidates including the converted interval T1 and integer multiples U×T1 of the converted interval T1, and a frequency-domain pitch period code indicating how many times the frequency-domain pitch period T is greater than the converted interval T1 is obtained. The frequency-domain pitch period code is output so that a decoding side can identify the frequency-domain pitch period T.
    Type: Application
    Filed: February 23, 2018
    Publication date: June 28, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro MORIYA, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Publication number: 20180182406
    Abstract: A frequency-domain sample interval corresponding to a time-domain pitch period L corresponding to a time-domain pitch period code of an audio signal in a given time period is obtained as a converted interval T1, a frequency-domain pitch period T is chosen from among candidates including the converted interval T1 and integer multiples U×T1 of the converted interval T1, and a frequency-domain pitch period code indicating how many times the frequency-domain pitch period T is greater than the converted interval T1 is obtained. The frequency-domain pitch period code is output so that a decoding side can identify the frequency-domain pitch period T.
    Type: Application
    Filed: February 23, 2018
    Publication date: June 28, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Patent number: 9947331
    Abstract: A frequency-domain sample interval corresponding to a time-domain pitch period L corresponding to a time-domain pitch period code of an audio signal in a given time period is obtained as a converted interval T1, a frequency-domain pitch period T is chosen from among candidates including the converted interval T1 and integer multiples U×T1 of the converted interval T1, and a frequency-domain pitch period code indicating how many times the frequency-domain pitch period T is greater than the converted interval T1 is obtained. The frequency-domain pitch period code is output so that a decoding side can identify the frequency-domain pitch period T.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: April 17, 2018
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Patent number: 9711158
    Abstract: An encoding technique encoding a sound signal at a low bit rate with reduced processing. The technique includes: an interval determination determining an interval T between samples corresponding to periodicity of an audio signal or an integer multiple of a fundamental frequency of the audio signal from a set S of candidates for the interval T; and a side information generating encoding the determined interval T to obtain side information. The interval determining determines the interval T from a set S of Y candidates (Y<Z) including Z2 candidates (Z2<Z) selected from among Z candidates for the interval T representable with the side information without depending on a candidate subjected to the interval determination in a previous frame a predetermined number of frames before the current frame and including a candidate subjected to the interval determination in the previous frame the predetermined number of frames before the current frame.
    Type: Grant
    Filed: January 18, 2012
    Date of Patent: July 18, 2017
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yusuke Hiwasaki, Yutaka Kamamoto
  • Patent number: 9640190
    Abstract: In a speech coding scheme based on a speech production model, such as a CELP-based scheme, an object of the present invention is to provide a decoding method that can reproduce natural sound even if the input signal is a noise-superimposed speech. The decoding method includes a speech decoding step of obtaining a decoded speech signal from an input code, a noise generating step of generating a noise signal that is a random signal, and a noise adding step of outputting a noise-added signal, the noise-added signal being obtained by summing the decoded speech signal and a signal obtained by performing, on the noise signal, a signal processing that is based on at least one of a power corresponding to a decoded speech signal for a previous frame and a spectrum envelope corresponding to the decoded speech signal for the current frame.
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: May 2, 2017
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yusuke Hiwasaki, Takehiro Moriya, Noboru Harada, Yutaka Kamamoto, Masahiro Fukui
  • Patent number: 9552821
    Abstract: A value of gain is updated so that the greater the difference between the number of bits or estimated number of bits in a code obtained by encoding a string of integer value samples obtained by dividing each sample in a sample string derived from an input audio signal in a given interval by gain before the update and a predetermined number B of allocated bits, the greater the difference between the gain before the update and the updated gain. A gain code corresponding to the updated gain and an integer signal code obtained by encoding a string of integer value samples obtained by dividing each sample in the sample string by the gain are obtained.
    Type: Grant
    Filed: May 29, 2013
    Date of Patent: January 24, 2017
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Patent number: 9319645
    Abstract: In encoding, index information indicating a group of coefficients that minimizes the sum of the error between the value of each sample and the value is obtained by multiplying the quantized value of each of a plurality of samples by a coefficient corresponding to the position of the sample. The coefficient is selected from a plurality of groups of predetermined coefficients corresponding to the positions of the samples. In decoding, a plurality of values corresponding to an input vector quantization index are obtained as decoded values corresponding to a plurality of sample positions. With the use of a group of predetermined coefficients corresponding to the plurality of sample positions and indicated by input index information, the values obtained by multiplying the decoded values and the coefficients, corresponding to the sample positions are output.
    Type: Grant
    Filed: July 4, 2011
    Date of Patent: April 19, 2016
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masahiro Fukui, Shigeaki Sasaki, Yusuke Hiwasaki, Shoichi Koyama, Kimitaka Tsutsumi
  • Patent number: 9230554
    Abstract: In encoding, the number of bits to be assigned to codes corresponding to noise or a pulse sequence obtained according to prediction analysis applied to time series signals included in a predetermined time interval is switched according to whether an index that indicates a level of periodicity and/or stationarity of input time series signals satisfies a condition that indicates high periodicity and/or high stationarity or a condition that indicates low periodicity and/or low stationarity, to acquire the codes corresponding to the noise and the pulse sequence. In decoding, a decoding mode for codes corresponding to noise or a pulse sequence included in codes corresponding to a predetermined time interval is switched according to the same criterion as that described above to decode the codes corresponding to the noise or the pulse sequence to acquire noise or a pulse sequence corresponding to the predetermined time interval.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: January 5, 2016
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yutaka Kamamoto, Yusuke Hiwasaki, Masahiro Fukui
  • Publication number: 20150194163
    Abstract: In a speech coding scheme based on a speech production model, such as a CELP-based scheme, an object of the present invention is to provide a decoding method that can reproduce natural sound even if the input signal is a noise-superimposed speech. The decoding method includes a speech decoding step of obtaining a decoded speech signal from an input code, a noise generating step of generating a noise signal that is a random signal, and a noise adding step of outputting a noise-added signal, the noise-added signal being obtained by summing the decoded speech signal and a signal obtained by performing, on the noise signal, a signal processing that is based on at least one of a power corresponding to a decoded speech signal for a previous frame and a spectrum envelope corresponding to the decoded speech signal for the current frame.
    Type: Application
    Filed: August 28, 2013
    Publication date: July 9, 2015
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yusuke Hiwasaki, Takehiro Moriya, Noboru Harada, Yutaka Kamamoto, Masahiro Fukui
  • Publication number: 20150088529
    Abstract: A value of gain is updated so that the greater the difference between the number of bits or estimated number of bits in a code obtained by encoding a string of integer value samples obtained by dividing each sample in a sample string derived from an input audio signal in a given interval by gain before the update and a predetermined number B of allocated bits, the greater the difference between the gain before the update and the updated gain. A gain code corresponding to the updated gain and an integer signal code obtained by encoding a string of integer value samples obtained by dividing each sample in the sample string by the gain are obtained.
    Type: Application
    Filed: May 29, 2013
    Publication date: March 26, 2015
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Publication number: 20150046172
    Abstract: A frequency-domain sample interval corresponding to a time-domain pitch period L corresponding to a time-domain pitch period code of an audio signal in a given time period is obtained as a converted interval T1, a frequency-domain pitch period T is chosen from among candidates including the converted interval T1 and integer multiples U×T1 of the converted interval T1, and a frequency-domain pitch period code indicating how many times the frequency-domain pitch period T is greater than the converted interval T1 is obtained. The frequency-domain pitch period code is output so that a decoding side can identify the frequency-domain pitch period T.
    Type: Application
    Filed: May 22, 2013
    Publication date: February 12, 2015
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Yutaka Kamamoto, Noboru Harada, Yusuke Hiwasaki, Masahiro Fukui
  • Patent number: 8724734
    Abstract: A coding method with a small error is provided. In the coding method of the present invention, a normalization value obtained from an input signal is corrected for an error calculated from an input and output in vector quantization and is then quantized. The coding method includes a normalization stage of normalizing the input signal in accordance with the normalization value of the input signal, calculated in each frame; a dividing stage of dividing the normalized frame into divided input signal sequences in accordance with a predetermined rule; a vector quantization stage of applying vector quantization to the divided input signal sequences to generate a vector quantization index; and a normalization value correction stage of correcting the normalization value of the input signal for the error obtained from the input and output in the vector quantization stage.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: May 13, 2014
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shigeaki Sasaki, Takeshi Mori, Hitoshi Ohmuro, Yusuke Hiwasaki, Akitoshi Kataoka, Kimitaka Tsutsumi
  • Patent number: 8711012
    Abstract: A plurality of samples are vector-quantized to obtain a vector quantization index and quantized values; bits are assigned in a predetermined order of priority based on auditory perceptual characteristics to one or more sets of sample positions among a plurality of sets of sample positions, each set having a plurality of sample positions and being given an order of priority based on the auditory perceptual characteristics, the number of bits not being larger than the number of bits obtained by subtracting the number of bits used for a code corresponding to the vector quantization index from the number of bits assigned for the code corresponding to the vector quantization index; and index information indicating a group of coefficients that minimizes the sum of the error between the value of each sample included in each of the sets of sample positions to which the bits are assigned and the value obtained by multiplying the quantized value of each sample included in the set of sample positions by a coefficient co
    Type: Grant
    Filed: July 4, 2011
    Date of Patent: April 29, 2014
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masahiro Fukui, Shigeaki Sasaki, Yusuke Hiwasaki, Shoichi Koyama, Kimitaka Tsutsumi
  • Publication number: 20140019145
    Abstract: In encoding, a frequency-domain sample sequence derived from an acoustic signal is divided by a weighted envelope and is then divided by a gain, the result obtained is quantized, and each sample is variable-length encoded. The error between the sample before quantization and the sample after quantization is quantized with information saved in this variable-length encoding. This quantization is performed under a rule that specifies, according to the number of saved bits, samples whose errors are to be quantized. In decoding, variable-length codes in an input sequence of codes are decoded to obtain a frequency-domain sample sequence; an error signal is further decoded under a rule that depends on the number of bits of the variable-length codes; and from the obtained sample sequence, the original sample sequence is obtained according to supplementary information.
    Type: Application
    Filed: March 26, 2012
    Publication date: January 16, 2014
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yutaka Kamamoto, Yusuke Hiwasaki, Masahiro Fukui
  • Publication number: 20130317814
    Abstract: In encoding, the number of bits to be assigned to codes corresponding to noise or a pulse sequence obtained according to prediction analysis applied to time series signals included in a predetermined time interval is switched according to whether an index that indicates a level of periodicity and/or stationarity of input time series signals satisfies a condition that indicates high periodicity and/or high stationarity or a condition that indicates low periodicity and/or low stationarity, to acquire the codes corresponding to the noise and the pulse sequence. In decoding, a decoding mode for codes corresponding to noise or a pulse sequence included in codes corresponding to a predetermined time interval is switched according to the same criterion as that described above to decode the codes corresponding to the noise or the pulse sequence to acquire noise or a pulse sequence corresponding to the predetermined time interval.
    Type: Application
    Filed: February 8, 2012
    Publication date: November 28, 2013
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yutaka Kamamoto, Yusuke Hiwasaki, Masahiro Fukui
  • Publication number: 20130311192
    Abstract: An encoding technique encoding a sound signal at a low bit rate with reduced processing. The technique includes: an interval determination determining an interval T between samples corresponding to periodicity of an audio signal or an integer multiple of a fundamental frequency of the audio signal from a set S of candidates for the interval T; and a side information generating encoding the determined interval T to obtain side information. The interval determining determines the interval T from a set S of Y candidates (Y<Z) including Z2 candidates (Z2<Z) selected from among Z candidates for the interval T representable with the side information without depending on a candidate subjected to the interval determination in a previous frame a predetermined number of frames before the current frame and including a candidate subjected to the interval determination in the previous frame the predetermined number of frames before the current frame.
    Type: Application
    Filed: January 18, 2012
    Publication date: November 21, 2013
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yusuke Hiwasaki, Yutaka Kamamoto